# AUR0173

## Error Message

`AUR0173: Expression error: invalid arrow parameter list in "{{expression}}"`

## Description

This error occurs when an arrow function expression is used with an invalid parameter list.

## Example Trigger

```html
<!-- ❌ Invalid parameter list -->
<div textcontent.bind="(a,,b) => a + b"></div>
```

## Solution

* Fix the arrow function syntax, or move the logic into the view-model.


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